Question

I am working on a site which displays products from a database in a listed format, so far so good. However, I would like to add a simple checkbox above which, when ticked, orders the list by price, lowest to highest (and also another one from highest to lowest). I have tried to do this but I’m having problems.

First I added a checkbox (see HTML below) labelled “order by lowest price”. Then I added a line to my php code just below the main database query (about 10 lines down my PHP code), which tries to append a piece of query language on the end of the database query, which is just above, however it doesn’t seem to work.

I just want to make it so that when the user checks the checkbox, it is sorted by cheapest to most expensive. What have I done wrong?

Note: ‘buynow’ is where the price data is stored for each row.

HTML

<form action="spain-holidays.php" method="post">
  <p>Order by lowest price:</p><input name="orderbyprice" type="checkbox" value="orderbyprice" />
</form>

PHP

<?php 

//connect
include ("db.connect.php");

//pagination
$per_page = 20;

$pages_query = mysql_query("SELECT COUNT('id') FROM `holidaytable` WHERE brandname = 'Spain'");
$count = mysql_result($pages_query, 0);
$pages = ceil(mysql_result($pages_query, 0) / $per_page);

$page = (isset($_GET['page'])) ? (int)$_GET['page'] : 1;
$start = ($page - 1) * $per_page;

echo '<p>There are '.$count.' holidays<hr></p><br /><br />';

//construct query and insert values

$query = mysql_query("SELECT * FROM holidaytable WHERE brandname = 'Spain' LIMIT $start, $per_page") or die(mysql_error());


//THIS IS THE LINE I ADDED HERE:

if (isset($_POST['orderbyprice'])) $query .= " ORDER BY buynow ASC";



while($rows = mysql_fetch_assoc($query)) {

    $name = $rows['name'];
    $id2 = $rows['id2'];
    $hotelname = $rows['hotelname'];
    $desc = $rows['desc'];
    $spec = $rows['spec'];
    $resort = $rows['resort'];
    $awtrack = $rows['awtrack'];
    $awthumb = $rows['awthumb'];
    $awimage = $rows['awimage'];
    $mthumb = $rows['mThumb'];
    $mlink = $rows['mlink'];
    $mimage = $rows['mimage'];
    $buynow = $rows['buynow'];
    $awcatid = $rows['awcatid'];
    $mcat = $rows['mcat'];
    $brandname = $rows['brandname'];


echo  "<div class='resultbox'>
<div class='resultboxtopbar'>
    <div class='hotelname'><h3>$hotelname</h3></div>
    <div class='price'><h3>From <strong>£$buynow</strong> $spec</h3></div>
</div>
<div class='resultboxmain'>
    <div class='resultboximage'><a href='$awtrack' target='_blank'><img src='$mimage' /></a></div>

        <h4>$resort, $brandname</h4>
        <p>$name</p>
        <p>$desc...</p>
        <div class='moreinfobutton'><input name='moreinfo' type='button' value='moreinfo' /></div>
</div>";

//more pagination, etc

Answer 1

mysql_query() does not return a string and therefore cannot be appended to. You should do something like this instead:

$sql = "SELECT * FROM holidaytable WHERE brandname = 'Spain' LIMIT $start, $per_page";

if (isset($_POST['orderbyprice'])) $sql .= " ORDER BY buynow ASC";

$query = mysql_query($sql) or die(mysql_error());